Very interesting for all kinds of reasons.
The High Buston site in Northumberland isn't shown at all. Is it no longer used for civil ATC?
The reported site at Rhu Stafnish on the Kintyre peninsula isn't shown. Explains why I couldn't detect any signals there some years ago.
There is more than just a VOR at St Abbs, Lands End, and Midhurst.
There is more than just a radar tower at Eaglescott in Devon.
The reported site on Anglesey is at Mona, not Valley, which explains why I never detected any strong ATC signals at Valley!
Some sites have just one circle centred on the transmitter site, some have a second or third circle which is offset somewhat. I wonder if this indicates some directional transmission/reception?
The most offset is Preston, and indicates some direction towards Dublin, which seems understandable.
I reserve the right to ignore people who have made no attempt to the read the manual, and expect others to do it for them.